--- a/s4-blog.sh	Mon Oct 25 23:25:56 2021 +0900
+++ b/s4-blog.sh	Tue Oct 26 13:16:29 2021 +0900
@@ -270,7 +270,7 @@
 	;;
     esac
   fi
-  href4="${blog_math:+Math} <a href=\"#bottom\" accesskey=\"b\" title=\"Shortcut: B${nl}to the Bottom\"> 末尾へ</a>"
+  href4="${blog_math:+<span id=\"mathjax\">Math</span>} <a href=\"#bottom\" accesskey=\"b\" title=\"Shortcut: B${nl}to the Bottom\"> 末尾へ</a>"
   $isgrpadmin &&
       href5="<a href=\"?blogseen+$rowid\" accesskey=\"s\" title=\"Shortcut: S${nl}State of Accesses\"> 読刻</a>"
   quizmodefile=$tmpd/quiz; rm -f "$quizmodefile"	# XXX: Global state
@@ -417,7 +417,7 @@
     echo "時間をおいてください(Visit later please)." | html p
     return
   fi
-  echo "${blog_math:+$mathjax}"
+  printf '%s' "${blog_math:+$mathjax}"
   echo '<table class="blog_replies"> <!-- blog:blog_showentry() main table -->'
   # If, nLimit = 50
   # show article:1, hide(2, 3), show(4, ...)